Believe in something that for convenience’s sake we might call “God,” but not a Christian.
Raised Quaker, and continue to consider myself one.
Roman Catholic
Episcopalian
(A theologically uberliberal Episcopalian, to be more specific ;))
Evangelical Charismatic Hopeful-Universalist Christian, member of the local Assembly of God. If C.S. Lewis had started a church, I’d probably join that one.
Church of the Brethren
Christian (Church of England, in the “woolly liberal” tradition, or Broad Church if you’re feeling charitable.)
Agnostic
Unitarian Universalist who attends an Episcopal church. During the weekly coffee-hour/debate/meet and greet I drink sherry.
Anglican considering becoming Roman Catholic.
I was raised Catholic, but no longer consider myself to be even remotely Christian. Now I’m bits of theist, buddist with a bit of Unitarian Universalist thrown in for good measure.
I don’t know what I’ll be tomorrow.
Atheist, although for interests of full disclosure I was raised Methodist and converted to the Russian Orthodox Church for a brief time in my early twenties.
I got better.
Wiccan monotheist with Christian and Hellenic leanings.
I’m not even an atheist, which could be considered the religion of not believing in god. I prefer to call myself an apatheist. I don’t care about any of it.
Lapsed Roman Catholic, with a twist of (lapsed) Luthern, thanks to my mother.
Continually toying with the idea of becoming Buddhist or Taoist, or Hindu.
Plan to become a Minister in the Universal Life Church this afternoon. 
Having said that, if I were stuck in a foxhole somewhere, I’d lay odds I’d be praying like a Baptist to the Lord Almighty to get me the hell out.
Raised Methodist, toyed with Episcopal for a few years, then converted to Roman Catholicism (24 years ago and counting).
Christian. More-or-less Southern Baptist. Theologically moderate, meaning that I annoy the people on both extremes equally.
Wiccan/non-secular Humanist
Christian (Reformed Presbyterian specifically)
Agnostic/Atheist (depending on what the definition of I AM is)